1. Field of the Invention
The present invention relates to an intra-aortic balloon pump apparatus, more particularly to an intra-aortic balloon pump apparatus that enables it to determine whether the inside of a balloon pump is maintained at a negative pressure.
2. Description of the Prior Art
Conventionally, an intra-aortic balloon pump apparatus is connected to its exclusive pressure source through its supply inlet for helium gas and adapted to inflate and deflate a balloon by means of helium gas. Such an intra-aortic balloon pump apparatus is inserted into the patient, either percutaneously or through an incision, and advanced until it lies within the thoracic aorta descendens. Then, the balloon is inflated and deflated in synchronous relationship with the pulsation of the heart so as to reduce the load on the left ventricle and increase the amount of coronary blood flow.
Since the apparatus is inserted into the patient's body with the balloon wrapped, the inside of the balloon has to be maintained at a negative pressure without causing the balloon to be inflated, so that a check valve and syringe have been utilized.
In the above-described conventional intra-aortic balloon pump apparatus, however, there is no way for determining whether the inside of the balloon is actually maintained at a negative pressure, even though it has been maintained at a negative pressure by a negative pressure source. If a cylindrical holder for holding the wrapped balloon is removed therefrom when the inside of the balloon has not been maintained at a negative pressure, the balloon is inflated, so that it may not be inserted into the patient's body.